How to delete a phantom sprint?

I have just upgraded Jira Agile from 5.0.0 to 6.1.6, and then gone through all of the Plan buttons on all of the projects to force a migration to the new sprint implementation. However, I am still getting the reminder that not all sprints have been migrated.

When I dump out the sprint migration db entry, I see:

mysql> SELECT * FROM AO_60DB71_RAPIDVIEW WHERE sprint_markers_migrated is null;

The last 2 are not Scrum propjects, and therefore should be ignored. But I am unaware of the "Test Board" that needs to be migrated. It does not exist anywhere that I can find it. It is also owned by a guy who left years ago.

This may be an artifact from some ancient bad migration, or a db corruption or something else equally bizarre. The integrity-checker sanity check says that everything is ok, but I still have this phantom board.

Hey everyone! My name is Sarah Schuster, and I'm a Customer Success Manager in Atlassian specializing in Jira Software Cloud. Over the next few weeks I will be posting discussion topics (8 total) to ...